Combustor heat shields have been used in the combustors of gas turbine engines. These heat shields are positioned between the combustor dome and the combustion chamber and are used to shield the combustor dome from the heat generated by ignited gases within the combustion chamber. Impingement openings in the combustor dome allow air to pass through the dome. The air then contacts the upstream surface of the heat shield to cool the heat shield by impingement and convection heat transfer. However, the air may not adequately cool the heat shield.
An increase in the effectiveness of cooling results in increased durability for the heat shields, and thus, reduces replacement frequency. One mechanism for increasing the effectiveness of heat shield cooling includes increasing the volume of air that passes through the impingement openings of the combustor dome. The increased air volume may increase heat shield cooling, but the quantity of cooling air available to the heat shield is generally restricted by the demand to cool other areas of the combustor and turbine engine.
Accordingly, it is desirable to provide heat shields for use in combustors that provide more effective cooling. In addition, it is desirable to provide combustors that exhibit increased cooling effectiveness. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.